Fig. 4

Correlation analyses for tags from the nucleoid and control samples. a Strand cross-correlations for the tags from the nucleoid sample and control. Grey line represents unsmoothed profile and red line corresponds to smoothing in 25-bp running window. The cross-correlation profile for the nucleoid has a non-trivial peak at 50 bp (the blue dot in the left panel). The tag cross-correlation profile for the control has only one peak corresponding to the tag length (the blue dot in the right panel). b Results of the strand auto-correlations analysis for the nucleoid sample and control. As in (a) grey line represents unsmoothed and red line represents smoothed profile. c Fourier analysis of the auto-correlation profiles shown in (b). The Fourier analysis reveals one dominant period of 93 bp in the auto-correlation profile for the nucleoid tags (indicated with the red dot)